Improved endothelial cell attachment on ePTFE vascular grafts pretreated with synthetic RGD-containing peptides

Objections: To assess endothelial cell (EC) attachment in seeding of expanded polytetrafluoroethylene (ePTFE) vascular prostheses by application of a new technique of coupling synthetic RGD-containing peptides with the graft surface. Design: Prospective, open study. Setting: University Department of Cardiovascular Surgery and Institute of Biochemistry. Materials and Methods: ePTFE vascular grafts (group I) uncoated (group 2) coated with fibronectin (group 3) coated with a RGD-containing peptide or (group 4) coated in a similar way to group 3 but without application of a RGD-peptide, were incubated for 30 min with adult human saphenous vein endothelial cells. After seeding, grafts were exposed to shear stress in an artificial flow circuit. EC attachment after seeding and retention after perfusion was assessed by scanning electron microscopy and image analysis. Main results: Both EC attachment and retention were significantly increased by coating with fibronectin in comparison to uncoated ePTFE. Graft coating with an RGD-peptide lend to the highest increase in EC attachment (30.6% +/- 2.1%) and retention after shear stress (62.9% +/- 7.5%) compared to fibronectin coated (26.0% +/- 3.3%/45.5% +/- 2.1%), uncoated (14.9% +/- 3.1%/13.9% +/- 7.9%) and similar coated ePTFE grafts without application of a RGD-peptide (10.5% +/- 1.1%/6.6% +/- 1.5%). Conclusions: EC attachment on uncoated ePTFE vascular prostheses is very weak. Our technique of coupling the ePTFE graft surface with cell adhesion promoting RGD-containing synthetic peptides significantly improved this decisive step in endothelial cell seeding of ePTFE grafts.